Lightweight, portable cooking stove

ABSTRACT

A small, lightweight, portable cooking stove that utilizes alcohol as fuel and is suitable for backpacking, hunting, camping and similar activities. The cooking stove includes a combustion chamber which encloses, contains and regulates the entire combustion process. The stove also includes an efficient fuel vaporizer, which is adapted to perform in unison with the combustion chamber, to effect the metered and efficient mixing of the air and fuel vapor. An integral, simple and convenient means is provided to vary the intensity and pattern of the heat output, thereby controlling the cooking performance of the stove. The stove achieves high heat output and efficiency, low fuel consumption, and superior cooking performance in a small, lightweight, portable, convenient, simple and integrated assembly.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation-in-part patent application ofapplication Ser. No. 10/951,128 filed Sep. 27, 2004, currently pending,the entire contents of which are incorporated herein by reference.

TECHNICAL FIELD

The invention is a small, lightweight, portable cooking stove that usesalcohol as fuel.

BACKGROUND AND SUMMARY OF THE INVENTION

Prior Art

Portable cooking stoves designed to use alcohol as a fuel are well knownto prior art. These are used by hikers, campers, backpackers, huntersand others who have a need to boil water or cook a hot meal in remotelocations or primitive conditions. As a fuel, alcohol has variousadvantages over petroleum based fuels. Alcohol is widely available,inexpensive, convenient, relatively innocuous and easy to handle. It canbe readily repackaged and safely carried in lightweight plastic bottles.Alcohol stoves are typically smaller and lighter than petroleum-fueledstoves. Alcohol stoves are typically also very simple, reliable and easyto use, and have few, if any moving parts. Because of these advantages,alcohol-fueled stoves are very popular in many parts of the world.However, in the United States they have had limited popularity. Thislimited popularity is primarily due to two factors.

The first factor that has limited the popularity of alcohol-fueledstoves in the United States is their overall poor performance. Under thebest conditions, the heat output from these stoves is marginal. In realoutdoor conditions of wind and weather, these stoves rapidly becomeincapable of cooking a meal. These stoves demonstrate a variety of formsand features that cause inefficient performance and wasted heat. Theoverall inefficient performance of alcohol stoves known to prior artalso causes an excessive consumption of fuel. This is undesirable bothdue to the increased cost of operating the stove, as well as theincreased weight of fuel that must be carried.

The second factor that has limited the popularity of alcohol-fueledstoves in the United States is the inability to effectively adjust theheat output of the stove. Often these stoves provide no manner of heatadjustment. When they do, it is commonly effected by means of some typeof snuffer in the form of a partial lid, cap or cover that is positionedin such a way that partially interferes with or throttles the flame.This method of adjusting the heat output has several disadvantages.Positioning or adjusting of the snuffer can be a rather awkwardundertaking and requires removing the cooking pot or reaching under it.This presents a danger of burning or scalding. Often the cooking potmust be completely removed from the stove and set aside whilepositioning the snuffer. Obstructing the flame in this way tends toproduce a small hot spot on the bottom of the cooking pan and preventsthe even distribution of heat for thorough and rapid cooking.

In summation, the two primary factors that have limited the popularityof alcohol stoves in the United States are their overall poorperformance and the inconvenience with which the heat adjustment iseffected. Similarly, petroleum-fueled stoves enjoy a broad popularityprimarily due to their advantages of high heat output and the ability toadjust this heat output for control of the cooking process. Theseadvantages are generally viewed as outweighing their numerousdisadvantages. The disadvantages include the need for bulky and heavymetal fuel containers, high operating cost, poor operation in wind orcold weather, need to constantly tend them during cooking, odor, dangerof fuel spills, complexity, poor reliability, the need to carrymaintenance kits, and the possibility of dangerous flare-ups whenlighting the stove. In light of these numerous disadvantages, theimportance of high heat output and adjustable cooking performance indetermining the overall utility and popularity of a stove is clearlyseen.

SUMMARY OF THE CURRENT INVENTION

Objectives

The current invention seeks to achieve a variety of improvements overthe portable cooking stoves which are known to prior art. The currentinvention is conceived and designed with the intent of achievingspecific objective for enhanced performance and convenience over theprior art.

It is an objective of this invention to achieve a high heat output andstable cooking performance suitable for fast and effective cooking in avariety of outdoor conditions of the wind and weather—attaining overallcooking performance which consistently meets or exceeds the performanceof petroleum-fueled stoves.

It is a further objective of this invention to achieve a high fuelefficiency, in order to minimize operating costs and the weight of fuelthat must be carried.

It is a further objective of this invention to provide a convenient andsimple means for adjusting the heat output of the stove to effectivelycontrol the cooking process.

It is a further objective of this invention to be small, lightweight andconveniently portable. When packed with a fuel bottle, the entire stoveshall be of a size that can be held in the palm of the hand and weighonly a few ounces. The entire invention is rendered convenientlyportable in a sturdy and compact package.

It is a further objective of this invention to be largely trouble free,simple, reliable and easy to use.

It is a further objective of this invention that it will cool quickly sothat is can be handled and stowed soon after use.

To achieve the above listed objectives, a portable cooking stove isdescribed wherein the several components of that stove are adapted toperform together as an integrated unit—all components being engineeredto operate in balanced synergy to maximize the overall performance andutility of the stove. The several components of the stove are adapted towork in concert to optimize as far as practicable the various fluidic,thermodynamic and heat transfer processes of the stove in a manner thatis both unobvious and unknown to prior art.

CONTENTS

Combustion Chamber

Stoves known to the prior art are typically intended to effect thecombustion process in the open air. Because the combustion process takesplace in the open air, there is no means for controlling the quantity ofair in contact with the combustion process. This produces a conditionknown in the field of thermodynamics as “excess air”. The condition ofexcess air occurs when a combustion process is provided with more airthan is required for the complete combustion of the fuel. This excessair removes heat from the combustion process, thereby reducing theefficiency of the combustion process.

The importance and benefits of providing a combustion chamber to createa controlled volume wherein the entire combustion process can beenclosed, contained and encompassed in order to maximize the heat outputof a cooking stove are well known and detailed in prior art. Pat. Nos.5,915,371 and 5,842,463 both described the functioning and theperformance benefits derived from the use of a combustion chamber tomaximize the heat output of a cooking stove. These inventions evendescribe a means for adjusting the draft to alter the airflow throughthe combustion chamber, thereby varying the heat output and adapting tovarious cooking requirements.

These inventions described combustion chambers that are intended to beused primarily with solid fuel, such as wood or charcoal. They areadapted to address the specific problems associated with the combustionof such solid fuels. These inventions are not engineered nor adapted tometer and direct the flow of combustion air to efficiently mix with theeffect the combustion of a vaporized fuel. These prior inventions do notconceive of the combustion chamber as integral with a specificcombustion source, such that both components might be optimized andadapted to operate in balanced synergy. The cooking stove of the currentinvention incorporates a combustion chamber that is specificallyengineered and adapted as a component within an integrated assembly, tometer and direct the flow of combustion air such that it efficientlymixes with and effects the combustion of a vaporized fuel.

The portable, alcohol-fueled cooking stove of the current inventioncomprises a combustion chamber which is engineered and adapted to createa controlled volume wherein the entire combustion process can beenclosed, contained and encompassed. The purpose of this combustionchamber is to meter, regulate and control the flow of combustion air, aswell as facilitating and promoting the mixing of the combustion air withthe vaporized fuel. The combustion chamber is adapted to specificallymeter and direct the flow of combustion air so as to maintain thestoichiometric ratio with a given quantity of fuel and optimize theefficiency of the combustion process.

Alcohol-fueled stoves known to prior art may optionally employ awindscreen which may encompass the stove to a greater or lesser extent.However, these windscreens are, by design, description and intent,adapted only to shield the stove from the deleterious effects ofcrosswinds. Unlike a true combustion chamber, these windscreens are notengineered, adapted nor intended to create a controlled volume whereinthe entire combustion process can be contained, regulated and optimized.The prior art does not consider these windscreens to be an integral partof the stove. The prior art consistently refers to these windscreens asancillary components, being separate from the stove proper—an optionalpiece to be employed as required to shelter the stove. These windscreensare not intended to be fundamental to the operation of the stove and arenot adapted to specifically meter and direct the flow of combustion airso as to optimize the efficiency and control the combustion process.

Fuel Vaporizer

Whereas the combustion chamber is designed to effectively meter andcontrol the flow of combustion air, the efficient operating of the stovealso relies on the effective generation an distribution of fuel vapor.The respective volumes of the combustion air and the fuel vapor must beadapted to alternately achieve a stoichiometric ratio of air to fuel formaximum combustion efficiency, or a rarified ratio of air to fuel forreduced heat output and control over the cooking process.

In order for alcohol fuel to burn, the liquid must be converted into avapor. Consequently, all alcohol-fueled stoves employ some means bywhich the liquid alcohol fuel can be vaporized. This typically takes theform of some manner of vessel containing liquid alcohol fuel which iscaused to be heated and thereby be converted to vapor. Alternately, someform of wick is used to effect the vaporization of the fuel. Theefficiency and rate at which the liquid fuel can be vaporized directlyaffects both the fuel consumption and the heat output of the stove.Stoves known to prior art do not effect the fuel vaporizing processefficiently and demonstrate excessive thermal losses. These excessivethermal losses serve to both reduce the heat output of the stove, aswell as increase the fuel consumption.

The inefficiency of the fuel vaporizing process of stoves known to priorart is caused by several factors. These fuel vaporizing devicestypically incorporate an excessive external surface area, both as aconsequence of their physical size and dimensions, as well as thedeliberate application of fins, ribs or other heat transferringfeatures. This excessive surface area causes the loss of heat to theenvironment primarily through convection. These fuel vaporizing devicestypically incorporate an excessive mass as a consequence of theirphysical size and dimensions, as well as deliberate application ofadditional mass. Tis excessive mass causes the loss of heat to thethermal mass of the fuel vaporizing device. These deliberateapplications of excessive surface area and excessive mass result from animproper understanding of the physical processes involved in the fuelvaporization. U.S. Pat. No. 4,164,930 clearly illustrates both of theseimpediments applied to prior art.

Many stoves known to prior art use some form of wick. The employment ofa wick significantly circumscribes the performance of the fuelvaporizer. The limited capacity of the wicking process, combined withboth the mass and volume of the wick material, render the use of a wickunsuitable where high heat output, small size and light weight are allrequired.

In addition to incorporating forms and features that are conducive tothe excess loss of heat, stoves known to prior art typically do notemploy an effective means for mixing the vaporized fuel thoroughly withthe combustion air. If the fuel vapor and combustion air are notthoroughly mixed in the proper area beneath the cooking pot, unburnedfuel vapor will escape and both the temperature and efficiency of thecombustion process will be reduced. To effectively mix the combustionair and fuel vapor it is necessary to induce turbulence in one or bothof the fluids. For maximum combustion efficiency, this turbulence mustbe created at the confluence of the two fluid flows.

The portable, alcohol-fueled cooking stove of the current inventioncomprises a fuel vaporizer which is engineered and adapted to minimizethe heat loss through the external surface area and mass as far aspracticable while maintaining the utility of the stove.

The volume of the vessel os specifically adapted to hold approximatelyto U.S. fluid ounces of fuel. This is the optimal fuel capacity of thefuel vaporizer. This limited volume enables the fuel vaporizer to haveminimal size and dimensions. This minimal size and dimensions reduce asfar as practicable both the thermal mass and external surface area ofthe fuel vaporizer. This minimizes the heat which is lost to the thermalmass and the external surface area of the fuel vaporizer, and providesthe maximum amount of energy available to effect the vaporization of theliquid fuel. At the same time two U.S. fluid ounces of fuel providesfuel sufficient enough to cook a typical meal for two people. By holdingno more fuel than is required to cook a meal, the thermal mass of thefuel is also minimized. This minimal fuel volume and thermal massreduces as far as practicable the heat lost to the thermal mass of thefuel. Consequently, the optimized size and dimensions of fuel vaporizerenable complete utility of the stove while minimizing heat loss.

The fuel vaporizer is also designed to accelerate the flow of the fuelvapor to induce a turbulent flow. By throttling the expanding vaporthrough an array of small orifices, jets of vapor are ejected from thefuel vaporizer. These jets are positioned and located so as to beinjected directly into the convective flow of the combustion air. Thismaximizes the interaction and mixing between the combustion air and thefuel vapor and creates a very efficient diffusion flame.

Adjustable Heat Output

In addition to achieving a high efficiency with the consequentadvantages of high, stable heat output and low fuel consumption, thecurrent invention also incorporates a means for simply and convenientlyadjusting the heat output to achieve effective and precise control overthe cooking process. This heat adjustment is achieved by metering andcontrolling the flow of combustion air within the combustion chamber.The flow of combustion air is controlled both in volume and locationwithin the combustion chamber.

The ability to control the cooking process by adjusting the heat outputof a stove is a primary attribute that defines the utility, convenienceand desirability of the stove. Without the facility for effectivelyadjusting the heat output, a stove is of limited utility and largelyunsuitable for cooking. Petroleum-fueled stoves effect the heatadjustment by directly throttling the fuel flow. This in turn reducesthe quantity of combustion air which is entrained by the fuel flow.

Alcohol-fueled stoves known to prior art often incorporate no means atall for adjusting the heat output. Those stoves which do provide a heatadjustment typically employ some type of snuffer in the form of apartial lid, cap or cover that is positioned in such a way to obstructor interfere with the flow of fuel vapor as it escapes from the fuelvaporizer. This method of adjusting the heat output has severaldisadvantages. Positioning or adjustment of the snuffer can be a ratherawkward undertaking and requires removing the cooking pot or reachingunder it. This presents a danger of burning or scalding. Often thecooking pot must be completely removed from the stove and set asidewhile placing the stuffer. Obstructing the flame in this way also tendsto produce a small hot spot on the bottom of the cooking pan andprevents the even distribution of heat for thorough and rapid cooking.

The portable, alcohol-fueled cooking stove of the current inventionincorporates a practical, convenient, safe and simple mechanism forregulating the heat output of the stove. This mechanism is quick andeasy to operate, and it achieves an effective control of the cookingprocess. This mechanism is integral with the stove and readilyaccessible on the outside of the stove. The heat output of the stove canbe precisely adjusted without removing the cooking pot or risking burns,scalds or other mishaps.

This adjustment of the heat output is effected by metering andcontrolling the flow of combustion air both in volume and in location.This metering and controlling of the combustion air flow modulates thecombustion process which is in contact with the fuel vaporizer, enablingthe temperature of the fuel vaporizer to be regulated. That is, byreducing the volume and redirecting the location of the combustion airwithin the combustion chamber the fuel vaporizer can be caused to becooled. As the fuel vaporizer is cooled, it generates less fuel vapor.This reduced flow of fuel vapor, being conditioned by and adapted to thereduced and redirected flow of combustion air, produces a lower overallheat output for the stove. This means of reducing the flow of fuelvapor, in concert with the reduced and redirected flow of the combustionair, allows an effective, convenient and precise control of the cookingprocess. This means of controlling the heat output also spreads the heatvery evenly throughout the top portion of the combustion chamber andaround the bottom and the sides of the cooking pot, enabling foods to becooked quickly and thoroughly without hot spots or burning.

Portability

In addition to the improvements in the heat output, efficiency, utilityand convenience of the current invention, it is also adapted to besmall, lightweight and easily portable. The various components areengineered as an integrated unit not only to facilitate the operation ofthe stove, but also to facilitate its portability and storage.

An important measure of the utility of a backpacking stove is howlightweight, simple and convenient it is to carry. Stoves known to priorart may typically consist of a half-dozen or more parts, with littlethought given to their packaging. This can render them bulky anddifficult to carry, with the potential for lost or damaged parts andadded complexity of setup.

All the components of the current invention nest together when packed,forming a single, compact unit in the shape of a hollow cylinder. Thiscylinder is proportioned to also contain a fuel bottle, whereby theentire invention is rendered conveniently portable in a sturdy andcompact package that weighs only a few ounces and can be comfortablyheld in the palm of the hand. This package is so efficient that when thefuel bottle is filled with fuel, less than ten percent of the packagecontains empty space. Being so contained in a single, integrated unit,all of the components are protected from loss of damage, and the stovecan be quickly unpacked and set up for use.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the present invention may be had byreference to the following Detailed Description when taken in connectionwith the accompanying Drawings, wherein:

FIG. 1 shows the preferred embodiment in a cutaway, elevation view ofthe assembled stove;

FIG. 2 shows the preferred embodiment in a plan view of the assembledstove;

FIG. 3 shows the preferred embodiment of the fuel vaporizer in aperspective view;

FIG. 4 shows the preferred embodiment in sectional elevation with thestove in use and configured to produce maximum heat output;

FIG. 5 shows the preferred embodiment in sectional elevation with thestove in use and configured to produce minimum heat output;

FIG. 6 shows the preferred embodiment in a cutaway, elevation view ofthe packed stove;

FIG. 7 shows the preferred embodiment in an exploded, perspective viewof the packed stove;

FIG. 8 shows an alternate embodiment of the fuel vaporizer in a planview;

FIG. 9 shows this alternate embodiment of the fuel vaporizer in acutaway, sectional elevation view;

FIG. 10 shows this alternate embodiment of the fuel vaporizer in aperspective view;

FIG. 11 shows this alternate embodiment of the fuel vaporizer insectional elevation when it is in use;

FIG. 12 shows an additional alternate embodiment of the fuel vaporizerin a plan view;

FIG. 13 shows this additional alternate embodiment of the fuel vaporizerin a perspective view;

FIG. 14 shows this additional embodiment of the fuel vaporizer in acutaway, elevation view;

FIG. 15 shows an additional alternate embodiment of the fuel vaporizerin a perspective view;

FIG. 16 shows this additional alternate embodiment of the fuel vaporizerin a cutaway, sectional elevation view;

FIG. 17 shows an additional alternate embodiment of the fuel vaporizeran obturating device in a perspective view;

FIG. 18 shows this additional alternate embodiment of the fuel vaporizerand obturating device in a sectional, elevation view;

FIG. 19 shows this additional alternate embodiment of the fuel vaporizerand obturating device in a plan view;

FIG. 20 shows this additional alternate embodiment of the fuel vaporizerand obturating device in an elevation view;

FIG. 21 shows an alternate embodiment of the combustion chamber andobturating device in a plan view;

FIG. 22 shows an additional alternate embodiment of the combustionchamber and obturating device in a plan view;

FIG. 23 shows an additional alternate embodiment of the combustionchamber and obturating device in a cutaway, elevation view;

FIG. 24 shows an additional alternate embodiment of the combustionchamber and obturating device in a cutaway, elevation view;

FIG. 25 shows an additional alternate embodiment of the combustionchamber and obturating device in a cutaway, elevation view, with theobturating device positioned to produce minimum heat output;

FIG. 26 shows this additional alternate embodiment of the combustionchamber and obturating device in a cutaway, elevation view, with theobturating device positioned to produce maximum heat output;

FIG. 27 shows an alternate embodiment of the assembled stove in a planview;

FIG. 28 shows this additional alternate embodiment of the assembledstove in a cutaway, elevation view;

FIG. 29 shows an additional alternate embodiment of the fuel vaporizerand obturating device in a plan view; and

FIG. 30 shows this additional alternate embodiment of the fuel vaporizerand obturating device in a cutaway, sectional elevation view.

N.B.: The material thicknesses of components shown in section in thesedrawings are approximately ten-thousandths of one inch. Consequently,the section thicknesses are shown in slightly exaggerated scale toidentify the sections.

DETAILED DESCRIPTION

General Configuration and Assembly

FIG. 1 shows a cutaway elevation view of the preferred embodiment of theassembled stove. FIG. 2 shows a plan view of the preferred embodiment ofthe assembled stove. FIG. 3 shows a perspective view of the preferredembodiment of the fuel vaporizer.

The preferred embodiment of the current invention includes a combustionchamber 101 which comprises a cylindrical wall 1 approximately sixinches in diameter and four inches in height. This cylindrical wall 1 isformed from a thin sheet of aluminum, approximately ten-thousandths ofone inch thick, being rolled into a cylinder and attached together atthe ends 17. The ends 17 are attached by means of rivets 15 that slideinto keyhole slots 16. The combustion chamber 101 is intended toalternately sit upon a base or a supporting surface 99 such that thebottom of the combustion chamber is fully closed and sealed off from theair.

The combustion chamber cylindrical wall 1 is perforated by a pluralityof circular ports 13 and 14. These ports 13 and 14 admit combustion airinto the combustion chamber 101 and meter and direct the flow of thiscombustion air. These ports 13 and 14 which perforate the combustionchamber wall 1 are arrayed in two sets.

The first set of ports 13 which perforates the combustion chamber wall 1is the primary set of air metering ports 13. There are eighteen ports inthe primary set of air metering ports 13. Each of the eighteen ports inthe primary set 13 is one-half inch in diameter. All of the ports of theprimary set 13 are coplanar and are arrayed angularly about thecombustion chamber cylindrical wall 1, being located approximatelyone-half inch above the bottom edge of the combustion chamber 101. Underthe influence of the natural convection currents resulting from thecombustion process, the primary set of ports 13 is adapted to meter theappropriate volume of air to form a stoichiometric ratio with a specificquantity of fuel vapor. The locations and positions of the primary airmetering ports 13 are adapted to provide a controlled and directed flowof combustion air to efficiently mix with and effect the combustion offuel vapor.

The second set of ports 14 which perforates the combustion chamber wall1 is the secondary set of air metering ports 14. There are six ports inthe secondary set of air metering ports 14. Each of the six ports in thesecondary set 14 is one-quarter inch in diameter. All of the ports ofthe secondary set are coplanar and arrayed angularly about thecombustion chamber cylindrical wall 1, being located approximately twoand one-quarter inches above the bottom of the combustion chamber 101.The ports of the secondary set 14 are intended to throttle and restrictthe flow of air into the combustion chamber, thereby rarifying thequantity of combustion air within the combustion chamber.

The combustion chamber 101 includes an obturating device 2 wherebyalternately either the primary set of air metering ports 13, or thesecondary set of air metering ports 14 may be blocked off in part or inwhole. By alternately blocking either the primary set 13 or thesecondary set 14 of air metering ports, both the volume and the flowpatterns of the combustion air within the combustion chamber can beregulated and controlled. By controlling both the volume and flowpatterns of the combustion air, the heat output and cooking performanceof the stove can be controlled an adjusted.

The obturating device 2 consists of a thin, strong, flexible strip ofaluminum approximately ten-thousandths of one inch thick and one andone-quarter inches wide. This aluminum strip is formed into acylindrical band by attaching the ends of the strip together. The endsof the strip are attached by means of a rivet 15 that slides into akeyhole slot. The cylindrical obturating band 2 thus formed has aninside diameter adapted to fit over the outside diameter of thecombustion chamber cylindrical wall 1. The diameter of the obturatingband 2 is adapted to fit securely over the combustion chambercylindrical wall 1, while being loose enough to be readily slid over thecombustion chamber cylindrical wall 1.

The combustion chamber 101 includes a means for supporting a cooking pot7. This pot supporting device comprises two steel rods 3, each rod 3being approximately five and one-half inches long and one-eighth inch indiameter. Both ends of each rod 3 pass through the combustion chambercylindrical wall 1 and are supported by the cylindrical wall 1. The rods3 are arranged parallel and coplanar, being spaced approximately threeinches apart. Being so arranged, the rods 3 form a rudimentary grillageupon which a cooking pot 7 may be supported. This grillage is positionedapproximately one inch down from the top of the combustion chamber 101.

In conjunction with the combustion chamber 101, the stove comprises afuel vaporizer 104 such that the combustion chamber 101 and fuelvaporizer 104 are engineered and adapted as an integrated unit—operatingin balanced synergy to effect a high heat output and fuel efficiency bymaintaining a stoichiometric ratio between the combustion air and fuel.

The fuel vaporizer 104 comprises a vessel fabricated from aluminum inthe shape of a shallow, cylindrical cup 4. This shallow, cylindrical,cup-shaped, aluminum vessel 4 is approximately two inches in diameterand is adapted to hold approximately two U.S. fluid ounces of fuel.

This shallow, cylindrical cup 4 includes a double wall 8. By means ofthis double wall 8 the interior volume of the shallow, cylindrical cup 4is divided into two chambers 10 and 11. The first chamber is an innerchamber 11. The inner chamber 11 forms a cylinder whose diameter isdefined by the inside diameter of the double wall 8. This cylindrical,inner chamber 11 is coaxial and concentric with the shallow, cylindricalcup 4. The second chamber is an outer chamber 10. The outer chamber 10is annular in form, this annulus being formed by the gap between theouter wall of the combustion chamber 101 and the double wall 8. Theouter, annular chamber 10 fully encircles the inner cylindrical chamber11. Said chambers are separated each from the other by the double wall8. The chambers have some connection and may enjoy limited intercourseby means of a plurality of small ports 9 at the base of the double wall8.

The inner, cylindrical chamber 11 has a diameter that is at least eightypercent of the overall diameter of the fuel vaporizer 104. Thismaximizes, as far as is practicable while maintaining the utility of thestove, the outside surface area of the inner, cylindrical chamber 11.This also minimizes, as far as is practicable while maintaining theutility of the stove, the thickness of the outer, annular chamber 10.These factors work together to maximize the rate of heat transfer andthe efficiency of heat transfer between the inner, cylindrical chamber11 and the outer, annular chamber 10.

The inner, cylindrical chamber 12 of the fuel vaporizer 104 is uncoveredat the top, thereby forming an open chamber. The contents of this open,inner chamber 11 may freely communicate with the air. The outer, annularchamber 10 is covered at the top, thereby forming a closed chamber. Thisis closure is interrupted only by a plurality of small orifices 12.There are approximately twenty two of these orifices 12 arrayed in acircular pattern. These orifices 12 are approximately twentyeighth-thousandths of one inch in diameter. The diameter of the circularpattern of these orifices 12 is approximately one-eighth of an inchsmaller than the overall diameter of the fuel vaporizer 104.

Configuration for Maximum Heat Output

FIG. 4 shows a section through the elevation view of the stove as it isset up for cooking use and configured for maximum heat output. A cookingpot 7 is shown placed upon the stove, being supported by the potsupporting rods 3. The cooking pot 7 has an outer diameter which issomewhat smaller than the inner diameter of the combustion chamber 101such that the cooking pot 7 is able to fit inside the combustion chamber101. The diameter of the cooking pot 7 is approximately five andfive-eighths inches. When the cooking pot 7 is seated upon the potsupporting rods 3 and located within the top of the combustion chamber101, the top of the combustion chamber 101, is for most of its area,obstructed and closed off by the cooking pot 7. The only opening of thetop of the combustion chamber 101 is an annular gap which exists betweenthe cooking pot 7 and the combustion chamber wall 1. This annular gaphas a width of about three-sixteenths of one inch. This annular gap actsas a flue and accelerates the combustion gases out of the top of thecombustion chamber 101. This greatly facilitates and strengthens thenatural convection process that draws air into the combustion chamberthrough the air metering ports 13 and 14. This annular gap alsoincreases the transfer of heat from the combustion gases to the cookingpot 7. As the combustion gases are accelerated through the annular gap,they give up heat to the cooking pot 7 as defined by the BernoulliPrinciple.

With the stove set up as shown in FIG. 4, the combustion chamber 101creates a controlled volume wherein the entire combustion process can beenclosed, contained and encompassed. The combustion chamber 101 isplaced upon some supporting surface or suitable base 99 such that thebottom of the combustion chamber 101 is fully closed off from intrudingairflow. The obturating band 2 of the combustion chamber 101 ispositioned to fully expose the primary set of air metering ports 13,thereby occluding the secondary set of air metering ports 14. Alcoholfuel 28 is poured into the inner, cylindrical chamber 11 of the fuelvaporizer 104. By means of the plurality of small ports 9 at the base ofthe double wall 8, the fuel flows into the outer, annular chamber 10 andseeks a common level within the inner chamber 11 and outer chamber 10.The fuel vaporizer 104 is placed in the center of the combustion chamber101, being set upon the same supporting surface or suitable base 99 thatsupports the combustion chamber 101. A cooking pot 7 is placed on thestove, obstructing the top of the combustion chamber 101 except for theannular flue which exists between the cooking pot 7 and the combustionchamber wall 1. The alcohol fuel 28 in the inner, cylindrical chamber 11of the fuel vaporizer 104 is ignited and combusts by virtue of its freecommunication with the air.

The combustion of the fuel 23 in the inner, cylindrical chamber 11causes the double wall 8 of the fuel vaporizer 104 to be heated. Theheating of the double wall 8 causes the heat to be conducted into theouter, annular chamber 10 of the fuel vaporizer 104. This heat causesthe fuel in the outer, annular chamber 10 to vaporize. Because thegeometry of the fuel vaporizer 104 is so adapted to maximize the flow ofheat from the inner chamber 11 to the outer chamber 10 and minimize theloss of heat from the exterior surface area and thermal mass, the rateof fuel vaporization in the outer, annular chamber 10 is maximized. Thevaporized fuel can only escape from the outer, annular chamber 10 viathe plurality of small orifices 12 which interrupt the top closure ofthe outer, annular chamber 10.

In passing through the plurality of small orifices 12, the fuel vapor isaccelerated such that jets of fuel vapor 26 are ejected from the fuelvaporizer 104. By virtue of their location along the top edge of theouter diameter of the fuel vaporizer 104, the jets of fuel vapor 26 areejected directly into the upwelling convection current of combustion air30 which has been metered and directed by the combustion chamber 101through the primary set of air metering ports 13. This forcefulconvergence of the fuel vapor 26 and combustion air 30 produceseffective mixing of the fuel and air and creates a hot, efficientdiffusion flame—the design and dimensions of the fuel vaporizer 104 andthe combustion chamber 101 being so adapted to operate together inbalanced synergy and produce a stoichiometric ratio of fuel and air. Thecombustion gases are directed against the bottom and around the sides ofthe cooking pot 7 to maximize heat transfer to the cooking pot 7. Inthis manner the cooking performance, heat output and fuel efficiency ofthe stove are maximized.

Configuration for Minimum Heat Output

Notwithstanding the employment illustrated in FIG. 4, where both theheat output and the efficiency of the stove are maximized, the stove canbe easily adjusted to reduce the heat output in order to effectively andconveniently control the cooking process. FIG. 5 shows a section throughthe elevation view of the stove as it is set up for cooking use andconfigured for minimum heat output. A cooking pot 7 is shown placed uponthe stove, being supported by the pot supporting rods 3. To adjust theheat output of the stove, the obturating band 2 is slid down to coverand block the primary set of air metering ports 13. With the obturatingband 2 fully occluding the primary set of air metering ports 13, thesecondary set of ports 14 is fully exposed. With the obturating band 2in this position, the primary set of air metering ports 13 is blocked,such that no air can enter the bottom half of the combustion chamber101. This creates an anaerobic atmosphere in the bottom half of thecombustion chamber 101. The absence of oxygen in this anaerobic zoneprevents combustion from occurring in and about the fuel vaporizer 104.Being physically removed from, and beneath, the combustion process 27,the fuel vaporizer 104 is caused to be cooled, thereby reducing the rateof vapor generation and altering the flow pattern of fuel vapor. Thequantity of fuel vapor is thereby adapted to, and conditioned by, thereduced volume and redirected flow of combustion air.

The fuel vapor diffuses into the top half of the combustion chamber 101,where it opportunistically mixes with oxygen in this rarified top zone.This forms a diverse and dynamic combustion process 27 which puts out areduced amount of heat while spreading out within the top of thecombustion chamber 101. This eliminates hot spots which impair theutility of a stove. In this manner a practical, simple and effectivecontrol is achieved over the heat output, the shape and location of thecooking flame, and the overall cooking performance of the stove. Thiscontrol is also very convenient and easy to use, as the obturating band2 is readily accessible on the outside of the combustion chamber 101.Adjusting the obturating band 2 can be accomplished without interferenceor removal of the cooking pot 7 simply by tapping it lightly to cause itto slide down and cover the primary set of air metering ports 13.

Consequently, the control of the stove is such that when the primary setof air metering ports 13 is exposed there is the maximum output of heatfrom the stove. Simply by sliding the obturating band 2 down to coverthe primary set of ports 13, the secondary set of ports 14 is opened andthe heat is quickly controlled and reduced. The primary set of ports 13might alternately be partially unblocked, allowing small quantities ofair into the bottom of the combustion chamber 101. This provideseffective and practical control over a range of heat outputs forimproved cooking performance.

Packaging and Portability

FIG. 6 shows a cutaway, elevation view of the packed stove. FIG. 7 showsa perspective, exploded view of the packed stove. These figuresillustrate how the stove is conceived as an integrated unit for packingan carrying. The cylindrical wall 1 of the combustion chamber 101 isformed from a thin, aluminum sheet which is attached together at itsends 17. The ends of this sheet can be unattached and the thin, aluminumsheet is sufficiently strong and flexible to be wrapped into a coilaround the cylindrical fuel vaporizer 104. Likewise, the obturating band2 of the combustion chamber 101 is formed from a thin, aluminum stripwhich is attached together at its ends. The ends of this strip can beunattached and the thin, aluminum band 2 is sufficiently strong andflexible to be wrapped into a coil around the coiled combustion chamberwall 1. The assemblage thereby constructed is in the form of a hollowcylinder approximately two and one-quarter inches in diameter and fourinches in length.

This hollow cylinder is of sufficient diameter and sufficient length toefficiently contain a four fluid ounce fuel bottle 5, four fluid ouncesbeing sufficient volume of fuel for several days hiking. The cap 6 ofthe fuel bottle 5 is of such size and geometry as to fit efficientlyinside the fuel vaporizer 104. The pot supporting rods 3 store alongsidethis cylindrical assemblage. Thus the entire invention is renderedconveniently portable in a sturdy, lightweight and compact package whichis completely self contained, comprising the entire stove and the fuelbottle. This package fits in the palm of the hand and weighs only a fewounces.

Alternate Embodiment of the Fuel Vaporizer

FIG. 8 shows a plan view of an alternate embodiment of the fuelvaporizer 131. FIG. 9 shows a cutaway elevation view of this alternateembodiment fuel vaporizer 131, and FIG. 10 shows a perspective view. Thealternate embodiment of the fuel vaporizer 131 is adapted to concentratea large amount of heat on a small, confined chamber 34. The alternateembodiment fuel vaporizer 131 also surrounds and envelopes this small,confined chamber 34 in such a way that very little heat can escape fromit. In this way the alternate embodiment of the fuel vaporizer 131 iscapable of achieving a high rate of fuel vaporization with theconcatenate effect of a high overall heat output for the stove. Thealternate embodiment fuel vaporizer 131 is potentially capable of evengreater heat output than the preferred embodiment 104 of the fuelvaporizer.

The alternate embodiment of the fuel vaporizer 131 comprises a vessel inthe shape of a shallow, cylindrical cup 31. This shallow, cylindricalcup 31 incorporates a double wall 32. By means of this double wall 32the interior volume of the shallow, cylindrical cup 31 is divided intotwo chambers 33 and 34. The first chamber 34 is an inner chamber. Theinner chamber 34 forms a cylinder whose diameter is defined by theinside diameter of the double wall 32. This cylindrical, inner chamber34 is coaxial and concentric with the shallow, cylindrical cup 31. Thesecond chamber 33 is an outer chamber. The outer chamber 33 is annularin form, this annulus being formed by the gap between the cylindricalcup 31 and the double wall 32. The outer, annular chamber 33 fullyencircles the inner, cylindrical chamber 34. Said chambers 33 and 34 areseparated by the double wall 32. The inner and outer chambers 33 and 34have some connection and may enjoy limited intercourse by means of aplurality of small ports 35 at the base of the double wall 32.

The outer, annular chamber 33 is open, being uncovered at the top,thereby forming an open chamber. The contents of this open, outer,annular chamber 33 may freely communicate with the air. The inner,cylindrical chamber 34 is closed, being covered at the top, therebyforming a closed chamber. This closure 41 is interrupted only by aplurality of small apertures 40. This plurality of small apertures 40 isarrayed radially and angularly about the top closure 41 of the inner,cylindrical chamber 34.

FIG. 11 shows a section view of the fuel vaporizer 131 in use. When thestove is in use, alcohol fuel 28 is poured into the outer, annularchamber 33 of the fuel vaporizer 131. By means of the plurality of smallports 35 at the base of the double wall 32, the fuel flows into theinner, cylindrical chamber 34 and seeks a common level within the innerchamber 34 and the outer chamber 33. The alcohol fuel 28 in the outer,annular chamber 33 of the fuel vaporizer 131 is ignited and causescombustion 38 by virtue of its free communication with the air.

The combustion 38 of the fuel 28 in the outer, annular chamber 33 causesthe double wall 32 of the fuel vaporizer 131 to be heated. Because ofthis heating action accomplished in the outer, annular chamber 33, thisouter, annular chamber 33 can be referred to as the heating chamber. Theheating of the double wall 32 causes heat to be conducted into theinner, cylindrical chamber 34 of the fuel vaporizer 131. This heatcauses the fuel 28 in the inner, cylindrical chamber 34 to vaporize.Because of this vaporizing action accomplished in the inner, cylindricalchamber 34, this inner, cylindrical chamber 34 can be referred to as thevaporizing chamber. The vaporized fuel can only escape from the inner,cylindrical, vaporizing chamber 34 via the plurality of small apertures40 which interrupt the top closure 41 of the inner, cylindrical,vaporizing chamber 34. As the fuel vapor escapes through this pluralityof small apertures 40, it is accelerated into jets 39 thereby entrainingand actively mixing with the combustion air.

The alternate embodiment 131 shares various features with the preferredembodiment fuel vaporizer 104 of the fuel vaporizer, as well asemploying important differences. Both embodiments of the fuel vaporizercomprise two, concentric, interconnected chambers separated by a doublewall. Both embodiments of the fuel vaporizer employ one open chamber togenerate heat by means of open combustion. Both embodiments of the fuelvaporizer employ one closed chamber to generate vaporized fuel andaccelerate this vapor into jets.

The essential difference between the preferred and alternate embodimentsof the fuel vaporizer is the reversal in the function of the inner andouter chambers. The preferred embodiment fuel vaporizer 104 is adaptedto next efficiently with the other components so that the stove can bestowed in a single, compact unit. This requirement dictates certainaspects of the preferred embodiment fuel vaporizer's 104 form, geometryand dimensions. These dictated aspects of the preferred embodiment fuelvaporizer's 104 form, geometry and dimensions necessitate certaincomprises that preclude the total optimization of the fuel vaporizer'sperformance. The primary compromise involves the heat which is lost fromthe outer, annular vaporizing chamber 10 through the outside wall of thefuel vaporizer 104.

The alternate embodiment fuel vaporizer 131 is engineered specificallyto maximize the rate of fuel vaporization and the heat output of thestove. The form and geometry of the alternate embodiment are notconstrained by packaging requirements or other such limitations. Thisfrees the alternate embodiment fuel vaporizer 131 to be fully optimizedfor heat output and fuel efficiency. By engulfing the inner, cylindricalvaporizing chamber 34 in combustion 38, its form and design are adaptedto minimize heat loss and produce the highest possible temperatures tovaporize and superheat the fuel 28. By providing the outer, annularheating chamber 33 with an outer perimeter, more oxygen is available forthe combustion process 38 therein. These adaptations enable thealternate embodiment fuel vaporizer 131 to achieve the highestefficiency and heat output.

Additional Alternate Embodiment of the Fuel Vaporizer

FIG. 12 shows a plan view of an alternate embodiment of the fuelvaporizer 135. FIG. 13 shows a perspective view of this alternateembodiment 135, and FIG. 14 shows a cutaway, sectional elevation view.The alternate embodiment of the fuel vaporizer 135 is provided withcylindrical duct 42 coaxial with the body of the fuel vaporizer. Thiscylindrical duct 42 extends thru the bottom of the fuel vaporizer andhas a height about equal to that of the fuel vaporizer 135. Thiscylindrical duct 42 is adapted to provide a source of combustion air tothe inner, annular chamber 48 of the fuel vaporizer 135. By providingcombustion air to the inner, annular chamber 48, a greater amount ofheat can be generated in the inner, annular chamber 48. In this way thealternate embodiment of the fuel vaporizer 135 is capable of achieving ahigh rate of fuel vaporization with the concatenate effect of a highoverall heat output for the stove. The alternate embodiment 135 ispotentially capable of even greater heat output than the preferredembodiment 104 of the fuel vaporizer.

The alternate embodiment 135 shares various features with the preferredembodiment 104 of the fuel vaporizer, and operates in a similar manner.The alternate embodiment of the fuel vaporizer 135 comprises a vessel inthe shape of a shallow, cylindrical cup 45. This shallow, cylindricalcup 45 incorporates a double wall 44. By means of this double wall 44the interior volume of the shallow, cylindrical cup 45 is divided intotwo chambers 47 and 48. The first chamber 48 is an inner chamber. Theinner chamber 48 comprises an annular volume whose inside diameter isdefined by the outside diameter of the cylindrical duct 42, and whoseoutside diameter is defined by the inside diameter of the double wall44. This annular, inner chamber 48 is coaxial and concentric with theshallow, cylindrical cup 45. The second chamber 47 is an outer chamber.The outer chamber 47 is annular in form, this annulus being formed bythe gap between the cylindrical cup 45 and the double wall 44. Theouter, annular chamber 47 fully encircles the inner, annular chamber 48.Said chambers 47, 48 are separated by the double wall 44. The inner andouter chambers 47, 48 have some connection and may enjoy limitedintercourse by means of a plurality of small ports 46 at the base of thedouble wall 44.

The outer, annular chamber 47 is closed, being covered at the top,thereby forming a closed chamber. This closure is interrupted only by aplurality of small apertures 43. The inner, annular chamber 48 is open,being uncovered at the top, thereby forming an open chamber. Thecontents of this open, inner, annular chamber 48 may freely communicatewith the air. The contents of this open, inner, annular chamber 48 aredirectly provided with a supply of combustion air thru the cylindricalduct 42.

Additional Alternate Embodiment of the Fuel Vaporizer

FIG. 15 shows a perspective view of an alternate embodiment of the fuelvaporizer 140. FIG. 16 shows a cutaway, sectional elevation view of thisalternate embodiment 140. The alternate embodiment of the fuel vaporizer140 is provided with cylindrical duct 53 coaxial with the body of thefuel vaporizer. This cylindrical duct 53 extends thru the center of thefuel vaporizer 140. This cylindrical duct 53 is adapted to provide asource of combustion air to the center of the fuel vaporizer 140. Byproviding combustion air to the center of the fuel vaporizer 140,complete combustion of the vaporized fuel can be effected.

The alternate embodiment 140 shares various features with the alternateembodiment 131 of the fuel vaporizer, and operates in a similar manner.The alternate embodiment of the fuel vaporizer 140 comprises a vessel inthe shape of a shallow, cylindrical cup 49. This shallow, cylindricalcup 49 incorporates a double wall 50. By means of this double wall 50the interior volume of the shallow, cylindrical cup 49 is divided intotwo chambers 54, 55. Chamber 55 is an inner chamber. The inner chamber55 comprises an annular volume whose inside diameter is defined by theoutside diameter of the cylindrical duct 53, and whose outside diameteris defined by the inside diameter of the double wall 50. This annular,inner chamber 55 is coaxial and concentric with the shallow, cylindricalcup 49. The second chamber 54 is an outer chamber. The outer chamber 54is annular in form, this annulus being formed by the gap between thecylindrical cup 49 and the double wall 50. The outer, annular chamber 54fully encircles the inner, annular chamber 55. Said chambers 54, 55 areseparated by the double wall 50. The outer and inner chambers 54, 55have some connection and may enjoy limited intercourse by means of aplurality of small ports 56 at the base of the double wall 50.

The inner, annular chamber 55 is closed, being covered at the top by acover 51, thereby forming a closed chamber. This cover 51 is interruptedonly by a plurality of small apertures 52. The outer, annular chamber 54is open, being uncovered at the top, thereby forming an open chamber.

Additional Alternate Embodiment of the Fuel Vaporizer

FIG. 17 shows a perspective view of an alternate embodiment of the fuelvaporizer 145. FIG. 18 shows a sectional elevation view of thisalternate embodiment 145. FIG. 19 shows a plan view and 20 shows anelevation view of this alternate embodiment 145. The alternateembodiment of the fuel vaporizer 145 is provided with cylindrical duct64 coaxial with the body of the fuel vaporizer. This cylindrical duct 64extends thru the center of the fuel vaporizer 145. This cylindrical duct64 is adapted to provide a source of combustion air to the center of thefuel vaporizer 145. By providing combustion air to the center of thefuel vaporizer 145, complete combustion of the vaporized fuel can beeffected.

The alternate embodiment 145 shares various features with the alternateembodiment 140 of the fuel vaporizer, and operates in a similar manner.The alternate embodiment of the fuel vaporizer 145 comprises a vessel inthe shape of a shallow, cylindrical cup 60. This shallow, cylindricalcup 60 incorporates a conical wall 58. By means of this conical wall 58the interior volume of the shallow, cylindrical cup 60 is divided intotwo chambers 68, 69. Chamber 69 is an inner chamber. The inner chamber69 comprises a substantially annular volume whose inside diameter isdefined by the outside diameter of the cylindrical duct 64, and whoseoutside surface is defined by the inside surface of the conical wall 58.This substantially annular, inner chamber 69 is coaxial and concentricwith the shallow, cylindrical cup 60. The second chamber 68 is an outerchamber. The outer chamber 68 is substantially annular in form, beingformed by the gap between the cylindrical cup 60 and the conical wall58. The outer, substantially annular chamber 68 fully encircles theinner, substantially annular chamber 69. Said chambers 68, 69 areseparated by the cylindrical wall 58. The outer and inner chambers 68,69 have some connection and may enjoy limited intercourse by means of aplurality of small ports 57 at the base of the cylindrical wall 58.

The inner, substantially annular chamber 69 is closed, being covered atthe top by a cover 59, thereby forming a closed chamber. This closure isinterrupted only by a plurality of small apertures 63. The outer,substantially annular chamber 68 is partially covered by an obturatingdevice 62. This obturating device 62 is slidably mounted on the outsideof the shallow cup 60 by means of the cylindrical collar 61. Thecylindrical collar 61 is actuated by means of a Scotch Yoke mechanism65, 66, 67. Rotating the rod 67 about its axis causes the levers 66 toengage the pins 65, alternately causing the pins to be raised orlowered. The pins 65 are affixed to the cylindrical collar 61. By meansof this slidable mounting, the obturating device 62 can be raised orlowered over the chamber 68. With the obturating device 62 in the raisedposition, the chamber 68 is substantially open to the air, allowingcombustion to occur in the chamber 68. With the obturating device in thelowered position, the chamber 68 is closed, extinguishing combustion inthe chamber 68. By so regulating the combustion in the chamber 68, theoverall heat output of the fuel vaporizer can be controlled.

Additional Alternate Embodiment of the Fuel Vaporizer

FIG. 29 shows a plan view of an alternate embodiment of the fuelvaporizer 180. FIG 30 shows a cutaway, sectional elevation view of thisalternate embodiment 180. The alternate embodiment 180 shares variousfeatures with the alternate embodiments 140 and 145 of the fuelvaporizer, and operates in a similar manner. The alternate embodiment ofthe fuel vaporizer 180 is provided with cylindrical duct 97 coaxial withthe body of the fuel vaporizer. This cylindrical duct 97 extends thruthe center of the fuel vaporizer 180. This cylindrical duct 97 isadapted to provide a source of combustion air to the center of the fuelvaporizer 180. By providing combustion air to the center of the fuelvaporizer 180, complete combustion of the vaporized fuel can beeffected.

The alternate embodiment of the fuel vaporizer 180 comprises a vessel inthe shape of a shallow, cylindrical cup 91. This shallow, cylindricalcup 91 comprises a double wall 98. By means of this double wall 98 theinterior volume of the shallow, cylindrical cup 91 is divided into twochambers. The cup 91 incorporates a plurality of ports 95, whichperforate the outer wall of the cup 91. The fuel vaporizer 180 comprisesan obturating device 92 in the shape of an inverted, shallow,cylindrical cup, which is rotatably mounted around the outsidecylindrical wall of the shallow, cylindrical cup 91. The obturatingdevice is so dimensioned to create an annular gap 93 between the edge ofthe obturating device 92 and the double wall 98. The obturating device92 incorporates a plurality of ports 94 which perforate the outercylindrical wall of the obturating device 92. These ports 94 of theobturating device 92 are executed such that they can be aligned with theports 95 of the shallow cylindrical cup 91, thereby opening the ports95. Alternately, these ports 94 can be misaligned with the ports 95, bymeans of a rotational displacement of the obturating device 92. Ports 94and ports 95 being so misaligned, thereby cause ports 95 to be closed.The rotational displacement of the obturating device is facilitated bythe tab 96. By so aligning the ports 94 and ports 95 combustion in theouter chamber can be regulated, whereby the overall heat output of thefuel vaporizer can be controlled.

Alternate Embodiments of the Combustion Chamber

FIG. 21 shows a plan view of an alternate embodiment of the combustionchamber 150. This alternate embodiment comprises a combustion chamber 69and an obturating device 70 which possess an elliptical planform.

FIG. 22 shows a plan view of an alternate embodiment of the combustionchamber 155. This alternate embodiment comprises a combustion chamber 71and an obturating device 72 which possess a rectangular planform.

FIG. 23 shows an elevation view of an alternate embodiment of thecombustion chamber 160. This alternate embodiment comprises a combustionchamber 73 having a primary set of air metering ports 76 which iseffected as a pattern of numerous small ports. The secondary set of airmetering ports 75, is also effected as a pattern of small ports.

FIG. 24 shows an elevation view of an alternate embodiment of thecombustion chamber 165. This alternate embodiment comprises a combustionchamber 77 having a primary set of air metering ports 80 which iseffected as a series of elongated slots. The secondary set of airmetering ports 79 is also effected as a pattern of elongated slots.

FIGS. 25 and 26 show elevation views of an alternate embodiment of thecombustion chamber and obturating device 170. This alternate embodimentcomprises an obturating device 82 which is rotatably mounted on theoutside of the combustion chamber 81. The obturating device 82incorporates a primary set of air metering ports 83 and a secondary setof air metering ports 85. The combustion chamber 81 incorporates aprimary set of air metering ports 84 and a secondary set of air meteringports 86. The primary ports 83 of the obturating device 82 coincide withthe primary ports 84 of the combustion chamber 81. The secondary ports85 of the obturating device 82 coincide with the secondary ports 86 ofthe combustion chamber 81. The primary ports 83 of the obturating device82 are angularly offset from the secondary ports 85, with respect to thecorresponding ports 84, 86 of the combustion chamber 81.

FIG. 25 shows the obturating device 82 rotatably positioned to close offthe primary ports 84 of the combustion chamber 81. In this position thesecondary ports 86 of the combustion chamber 81 are opened.

FIG. 26 shows the obturating device 82 rotatably positioned to close offthe secondary ports 86 of the combustion chamber 81. In this positionthe primary ports 84 of the combustion chamber 81 are opened.

Alternate Embodiment of the Cooking Stove

FIG. 27 shows a plan view of an alternate embodiment of the cookingstove 175. FIG 28 shows a cutaway, elevation view of the alternateembodiment of the cooking stove 175. This alternate embodiment comprisesa combustion chamber 88. The combustion chamber 88 is full encircled bya cylindrical wall 87. The cylindrical wall 87 has a diameter somewhatgreater than the diameter of the combustion chamber 88, such that anannular hap exists between the outside diameter of the combustionchamber 88 and the inside diameter of the cylindrical wall 87. Thecylindrical wall 87 is intended to alternately sit upon a base or asupporting surface such that the bottom of the cylindrical wall 87 isfully closed and sealed off from the air. The bottom of the combustionchamber 88 is raised above the bottom above of the cylindrical wall 87,forming a gap which leaves the bottom of the combustion chamber 88 open.

The cooking stove 175 comprises the fuel vaporizer 145. The fuelvaporizer 145 is supported at the bottom of the combustion chamber 88 bymeans of two supports 90 and the rod 67 which pass thru openings in thecylindrical wall 87. The combustion chamber 88 sits upon the supports 90and the rod 67. In this way the fuel vaporizer 145, the combustionchamber 88, and the cylindrical wall 87 form an integrated assembly ofthe cooking stove 175.

In operation, combustion air is drawn down thru the annular hap betweenthe combustion chamber 88 and the cylindrical wall 87. This arrangementof the combustion chamber 88 and the cylindrical wall 87 creates a heatexchanger that preheats the combustion air as it is draw thru theannular gap. The preheated combustion air enters into the combustionchamber 88 thru the open bottom, where it mixes with the vaporized fuelgenerated by the fuel vaporizer 145 and combusts. The heat output of thestove can be adjusted by moving the obturating device 62, by means ofrotating the rod 67 which is accessible on the outside of thecylindrical wall 87.

This embodiment of the stove could alternately comprise the fuelvaporizer 180 in place of the fuel vaporizer 145, and still maintain thesame principles, function and operation.

Advantages of the Current Invention

Advantages of the Preferred Embodiment

It can be seen that the portable, alcohol-fueled cooking stove of thecurrent invention is novel in that it employs a combustion chamberdesigned to create a controlled volume wherein the entire combustionprocess can be enclosed, contained and encompassed, thereby regulatingand controlling the flow and mixing of the combustion air with thevaporized fuel. This combustion chamber is engineered and adapted towork in balanced synergy with a fuel vaporizer. In combination, thesecomponents operate to maintain a stoichiometric ratio of air and fuel toeffect a very efficient and high temperature combustion process. Thishigh heat output and balanced combustion also produce stable performanceacross a wide range of operating conditions and variations of wind andweather. This employment of a combustion chamber and a fuel vaporizerengineered as a unit operating in balanced synergy to maximize theefficiency, temperature and stability of the combustion and cookingprocesses is both insightful and unknown to prior art.

It can be further seen that the portable, alcohol-fueled cooking stoveof the current invention is novel in that it employs a fuel vaporizerengineered to minimize the loss of energy in the fuel vaporizing processas far as practicable, while maintaining the utility of the stove. Thisis achieved through minimizing the external surface area and mass of thefuel vaporizer through improvements in the geometry, design andconfiguration of the fuel vaporizer, while providing optimized fuelcapacity for convenient cooking. These improvements in the geometry,design and configuration of the fuel vaporizer produce a significant andmeasurable increase in the efficiency of the fuel vaporizing process.These improvements in the geometry, design and configuration of the fuelvaporizer, which produce a significant and measurable increase in theefficiency of the fuel vaporizing process, are persistently absent fromthe prior art.

It can be further seen that the portable, alcohol-fueled cooking stoveof the current invention is novel in that it employs a combustionchamber which is provided with a plurality of air metering ports. Inconjunction with these air metering ports, the combustion chamberemploys an obturating device whereby various of the ports might bealternately blocked or unblocked in order to meter and regulate thevolume, flow and location of the combustion air within the combustionchamber. By means of this metering, directing of regulating of thecombustion air, the fuel vaporizer can be caused to be cooled, therebyreducing the rate of vapor generation and altering the flow pattern offuel vapor. In this manner a practical, simple and effective control isachieved over the heat output, the shape and location of the cookingflame, and the overall cooking performance of the stove. This method ofcontrol causes the heat to be spread evenly throughout the top portionof the combustion chamber, resulting in a uniform cooking temperatureand preventing hot spots that can scorch or burn food. This method ofregulating the cooking performance of the stove by means of controllingthe volume, flow and location of the combustion air, with theconcatenate effect of cooling the fuel vaporizer and reducing the flowof fuel vapor, is deviceful and unique.

It can be further seen that the portable, alcohol-fueled cooking stoveof the current invention is novel in that it is conceived as anintegrated unit for packing and carrying. The various components of thestove nest together when packed, forming a compact, sturdy unit in theshape of a hollow cylinder, which is also proportioned to contain a fuelbottle. Being thus packed, the entire stove, including fuel, forms atightly integrated assembly which fits in the palm of the hand andweighs only a few ounces. So efficient is this nesting of components,that when packed with a full fuel bottle the stove has over ninetypercent of its volume filled. Such an efficient nesting of the variouscomponents of the stove, with the inclusion of the fuel bottle, into asingle, compact and sturdy unit is inventive and imaginative.

In addition to the specific features, adaptations and forms that renderthe current invention both novel and an unobvious improvement over priorart, there is a further, compelling testament to the innovation of thecurrent invention. Alcohol-fueled cooking stoves for backpacking andcamping are currently available in well over a dozen forms, designs andconcepts—either commercially or through published “Do-it-Yourself”instructions. The current invention exhibits a significantly higher heatoutput, as measured objectively by the time required to boil a givenquantity of water, than any currently published performancespecifications for any alcohol-fueled backpacking stove. The stove ofthe current invention exhibits significantly lower fuel consumption, asmeasured objectively by the fuel required to boil a given quantity ofwater, than any currently published performance specifications for anyalcohol-fueled backpacking stove.

In addition to the significant and measurable improvements in heatoutput and fuel efficiency of the current invention when compared toother alcohol-fueled stoves known to prior art, there is a further,prevailing testament to the ingenuity and improvement of the currentinvention. The performance of the current invention has been tested in avariety of operating conditions against petroleum-fueled backpackingstoves. The current invention consistently meets or exceeds the overallcooking performance of petroleum-fueled stoves, as measured objectivelyby the total time required to cook a typical, prepackaged, two servingmeal of rice. The current invention consistently meets or exceeds thefuel efficiency of petroleum-fueled stoves, as measured objectively bythe gross weight of fuel required to cook a typical, prepackaged, twoserving meal of rice. The current invention also exhibits superior highaltitude and cold weather performance than many petroleum-fueled stoves.

Advantages of the Alternate Embodiments of the Fuel Vaporizer

It can be seen that the alternate embodiment of the fuel vaporizer isnovel in that the inner, cylindrical, vaporizing chamber is fullyencircled by the outer, annular, heating chamber. This configurationcauses a greater amount of heat to be concentrated in the inner,cylindrical, vaporizing chamber effecting a high rate of fuelvaporization and high heat output. This adaptation of a fuel vaporizerhaving two, interconnected chambers whereby the inner, cylindrical,vaporizing chamber is fully encircled by the cuter, annular, heatingchamber enables levels of convenience, safety and performance which areunknown to prior art.

It must be noted that a superficially similar device is known to priorart. This superficially similar device is known from publishedspecifications to produce a greater heat output when compared to otherconfigurations of alcohol stoves known to prior art. However, thecurrent invention differs fundamentally from the prior art and is asignificant improvement over the prior art.

Whereas the current invention employs a single vessel that comprisestwo, interconnected chambers, the superficially similar device known toprior art employs two, separate vessels. The primary vessel is thevaporizing vessel. This vessel is substantially closed except for aplurality of small apertures and a filling port whereby the vessel isprovided with fuel. This filling port is subsequently plugged and thevessel is caused to be heated, whereby the fuel inside the vessel isvaporized and escapes through the plurality of small apertures. Thesecond vessel is employed to heat the primary, vaporizing vessel. Thesecond vessel is in the form of a small tray or saucer. The primary,vaporizing vessel is placed in this small tray or saucer shaped vesseland fuel is poured into this tray or saucer shaped vessel. Thecombustion of the fuel in this tray or saucer shaped vessel provides theheat for vaporizing the fuel in the primary, vaporizing chamber.

The use of two, separate vessels causes this superficially similardevice to be both inconvenient and dangerous. The need to fill two,separate vessels is cumbersome and leads to spillage of fuel. Fillingthe vaporizing vessel through a small filling port requires the use of afunnel or similar device. In addition, the fuel must be premeasured asthe fuel level cannot be seen inside the vessel. The plug for thefilling port can be lost, rendering the stove inoperable. Alternately,the vaporizing vessel may have a separate lid which must be removed forfilling. This separate lid is inconvenient and cumbersome with thepotential to be lost or damaged, rendering the stove inoperable.Finally, as the vaporizing vessel is substantially closed except for theplurality of small apertures, the vaporizing vessel can be overheatedand present an explosion hazard.

The current invention, being a single vessel comprising two,interconnected chambers, corrects all of the above shortcomings. Fuel isconveniently poured into the open, outer, annular chamber where itslevel can be easily seen. Graduations may be provided on the side of thevessel to accurately display the fuel volume. No plugs, funnels or otherloose pieces are required. Must important, the inner, vaporizing chambercannot be overpressurized and cannot explode. As the inner, vaporizingchamber enjoys intercourse with the open, outer annular chamber by meansof a plurality of small apertures at the base of the double wall, if thepressure in the vaporizing chamber becomes too high, it simply displacesliquid fuel and escapes harmlessly. The employment of two interconnectedchambers in a single vessel, with the concomitant improvements in theconvenience, utility and safety of the current invention, is asignificant breakthrough.

Alternate and Closing

Notwithstanding specific descriptions and details listed herein for thepurposes of illustration, it must in no way be construed that thesespecific descriptions and details in any way limit or circumscribe thescope of the invention. Various specific ramifications of the currentinvention are anticipated.

It is anticipated that the combustion chamber may be made adjustable indiameter such that cooking pots of various sizes can be properlyaccommodated.

It is anticipated that various, alternate means may be employed forsecuring together the ends of the combustion chamber cylindrical walland likewise the ends of the obturating band.

It is anticipated that the stove may be made larger.

It is anticipated that the stove may employ a windscreen or air jacketto enclose the combustion chamber, thereby providing additionalprotection from extremes of wind and weather.

It is anticipated that the combustion chamber may incorporate an arrayof dimples or ribs arranged to facilitate the centering of the cookingpot.

It is anticipated that various forms of shrouding or ducting may beemployed to direct the flow of combustion air and facilitate the mixingof the combustion air and fuel vapor.

It is anticipated that the combustion chamber may employ divers meansfor effecting the metering and control of the combustion air flow.

It is anticipated that the stove may be made of more rigid and heavymaterial whereby it would be suitable for use when portability is not aprimary concern.

It is anticipated that the pot supporting device may take a variety ofalternate forms.

It is anticipated that the fuel vaporizer may employ divers means foreffecting the vaporizing of the liquid fuel.

It is anticipated that provision might be made for supporting a largercooking pot, frying pan, skillet, or similar cooking utensil on thestove.

Notwithstanding specific descriptions and details listed herein for thepurposes of illustration, and notwithstanding various specificramifications and embodiments listed above, it must in no way beconstrued that these specific descriptions, details, embodiments orramifications in any way limit or circumscribe the scope of theinvention.

Although preferred embodiments of the invention have been illustrated inthe accompanying Drawings and described in the foregoing DetailedDescription, it will be understood that the invention is not limited tothe embodiments disclosed, but is capable of numerous rearrangements,modifications, and substitutions of parts and elements without departingfrom the spirit of the invention.

1. A lightweight portable cooking stove comprising the combination of: acombustion chamber comprising: a substantially imperforate cylindricalwall having an upper end and a lower end, the lower end for engaging asupporting surface; the wall having a defined diameter and comprising afirst row of relatively large substantially equally spaced ports and asecond row of relatively small equally spaced ports, the first andsecond rows of ports separated by a predetermined longitudinal distance;an obturating device supported on and longitudinally and rotationallymovable relative to the cylindrical wall for at least partially coveringeither the first row or the second row of ports thereby controlling boththe volume and flow of air into the combustion chamber; and means forsupporting a cooking pot within the wall of the combustion chamberwherein a lower portion of the cooking pot is located within the upperend of the wall of the combustion chamber; a fuel vaporizer supported bythe support surface and axially aligned with the wall of the combustionchamber, the fuel vaporizer comprising: an outer chamber defined by afirst right circular cylinder having an upper end, a lower end, an outersurface, an inner surface, and a first imperforate bottom wall extendingacross the entirety of the lower end; an inner chamber defined by asecond right circular cylinder having an upper end, a lower end, anouter surface an inner surface, and a second imperforate bottom wallextending across the entirety of the lower end thereby defining an innerfuel receiving chamber; the inner chamber axially aligned within theouter chamber; the outer surface of the second right circular cylinderspaced apart from the inner surface of the first right circular cylinderto defined an annularly spaced outer fuel vaporizing chambertherebetween; a top wall extending across the entirety of the upper endof the outer fuel vaporizing chamber, the top wall comprising aplurality of apertures formed therethrough at substantially equallyspaced intervals around the outside surface of the first right circularcylinder and the inside surface of the second right circular cylinder tofacilitate the passage of vaporized fuel from the outer fuel vaporizingchamber into the combustion chamber; at least one opening extendingbetween the inner fuel receiving chamber and the outer fuel vaporizingchamber and located adjacent to the lower end of the outer fuelvaporizing chamber; a cooking pot comprising a right circular cylinderhaving an outside diameter smaller than the defined diameter of the wallof the combustion chamber, the right circular cylinder of the cookingpot comprising an outer surface and an inner surface; the cooking potfurther comprising a substantially planar bottom wall comprising anextension of and extending substantially perpendicular to the outer wallof the cooking pot; whereby air entering the first plurality of portsextending through the combustion chamber wall mixes with vaporized fueldischarged through the apertures in the top wall of the outer fuelvaporizing chamber to form a stoichiometric ratio of mixed fuel and airthereby producing products of combustion having both maximum heatproduction and maximum fuel efficiency; the products of combustionengaging the bottom wall and outer surface of the cooking pot to effectmaximum heat transfer thereto.
 2. The cooking stove according to claim 1wherein the wall of the combustion chamber comprises a metal sheetdefined by first and second ends, the first and second ends removablyfastened together by rivets secured on the first end for engagement withrivet receiving orifices on the second end.
 3. The cooking stoveaccording to claim 1 wherein the obturating device comprises a rightcylindrical band movably coupled about the wall of the combustionchamber, the band having a longitudinal dimension which operativelyenables airflow through one of the first or second rows of ports whilepreventing airflow through the other of the first or second rows ofports.
 4. The cooking stove according to claim 1 wherein the means forsupporting a cooking pot within the wall comprises at least one rodextending through orifices perforated in the upper end of the wall andsupported by the wall.
 5. A lightweight portable cooking stovecomprising the combination of: a combustion chamber comprising: asubstantially imperforate cylindrical wall having an upper end and alower end, the lower end for engaging a supporting surface; the wallhaving a defined diameter and comprising a first row of relatively largesubstantially equally spaced ports and a second row of relatively smallsubstantially equally spaced ports, the first and second rows of portsseparated by a predetermined longitudinal distance; an obturating devicesupported on and longitudinally and rotationally movable relative to thewall for substantially covering either the first row or the second rowof ports thereby controlling both the volume and the rate of air flowinto the combustion chamber; and means for supporting a cooking potwithin the wall of the combustion chamber wherein a lower portion of thecooking pot is located within the upper end of the wall of thecombustion chamber; a fuel vaporizer supported by the support surfaceand axially aligned with the wall of the combustion chamber, the fuelvaporizer comprising: an outer chamber defined by a first right circularcylinder having an upper end, a lower end, an outer surface, an innersurface, and a first imperforate bottom wall extending across theentirety of the lower end; an inner chamber defined by a second rightcircular cylinder having an upper end, a lower end, an outer surface, aninner surface, and a second imperforate bottom wall extending across theentirety of the lower end thereby defining an inner fuel vaporizingchamber; the inner chamber axially aligned within the outer chamber todefine an annular outer fuel receiving chamber therebetween; a top wallextending across the entirety of the upper end of the inner chamber, thetop wall comprising a plurality of apertures formed therethrough atsubstantially equally spaced intervals around a circle concentric withand adjacent to the inside surface of the inner right circular cylindercomprising the fuel vaporizing chamber to facilitate the passage ofvaporized fuel from the inner fuel vaporizing chamber into thecombustion chamber; at least one opening extending between the innerfuel vaporizing chamber and the outer fuel receiving chamber and locatedadjacent to the lower end of the outer chamber; a cooking pot comprisinga right circular cylinder having an outside diameter smaller than thedefined diameter of the wall of the combustion chamber, the rightcircular cylinder of the cooking pot comprising an outer surface and aninner surface; the cooking pot further comprising a substantially planarbottom wall comprising an extension of and extending substantiallyperpendicular to the outer wall of the cooking pot; whereby air enteringthe first plurality of ports extending through the combustion chamberwall mixes with vaporized fuel discharged through the apertures in thetop wall of the inner fuel vaporizing chamber to form a stoichiometricratio of mixed fuel and air thereby producing products of combustionhaving both maximum heat production and maximum fuel efficiency; theproducts of combustion engaging the bottom wall and outer surface of thecooking pot to effect maximum heat transfer thereto.
 6. The cookingstove according to claim 5 wherein the wall of the combustion chambercomprises a metal sheet defined by first and second ends, the first andsecond ends removably fastened together by rivets secured on the firstend for engagement with rivet receiving orifices on the second end. 7.The cooking stove according to claim 5 wherein the obturating devicecomprises a right cylindrical band movably coupled about the wall of thecombustion chamber, the band having a longitudinal dimension whichoperatively enables airflow through one of the first or second rows ofports while preventing airflow through the other of the first or secondrows of ports.
 8. The cooking stove according to claim 5 wherein themeans for supporting a cooking pot within the wall comprises at leastone rod extending through orifices perforated in the upper end of thewall and supported by the wall.
 9. A lightweight portable cooking stovecomprising the combination of: a combustion chamber comprising: asubstantially imperforate cylindrical wall having an upper and a lowerend, the lower end for engaging a supporting surface; the wall having adefined diameter and comprising a first row of relatively largesubstantially equally spaced ports and a second row of the relativelysmall substantially equally spaced ports, the first and second rows orports separated by a predetermined longitudinal distance; an obturatingdevice supported on and longitudinally and rotationally movable relativeto the wall for at least partially covering one of either the first orthe second row of ports thereby controlling both the volume and rate ofair flow into the combustion chamber; and means for supporting a cookingpot within the wall of the combustion chamber wherein a lower portion ofthe cooking pot is located within the upper end of the wall of thecombustion chamber; a fuel vaporizer supported by the support surfaceand axially aligned with the wall of the combustion chamber, the fuelvaporizer comprising: an outer chamber defined by a first right circularcylinder having an upper end, a lower end, an outer surface, an innersurface, and a first imperforate bottom wall extending across theentirety of the lower end; an inner chamber defined by a second rightcircular cylinder having an upper end, a lower end an outer surface, aninner surface, and a second imperforate bottom wall extending across theentirety of the lower end; the inner chamber axially aligned within theouter chamber and the outer surface of the inner right circular cylinderand spaced apart from the inner surface of the first enclosure to definean outer annular fuel receiving chamber therebetween; a rightcylindrical duct coaxial with the inner and outer chambers positionedwithin the inner surface of the inner chamber to facilitate providingair for combustion about the inner chamber comprising the center of thefuel vaporizer; a top wall extending across the entirety of the upperend of the outer fuel vaporizing chamber, the top wall comprising aplurality of apertures formed therethrough at substantially equallyspaced intervals concentric with the inside surface of the inner rightcircular cylinder to facilitate the passage of vaporized fuel into thecombustion chamber; at least one opening extending between the innerfuel receiving chamber and the outer fuel vaporizing chamber and locatedadjacent to the lower end of the outer chamber; a cooking pot comprisinga right circular cylinder having an outside diameter smaller than thedefined diameter of the wall of the combustion chamber, the rightcircular cylinder of the cooking pot comprising an outer surface and aninner surface; the cooking pot further comprising a substantially planarbottom wall comprising an extension of and extending substantiallyperpendicular to the outer wall of the cooking pot; whereby air enteringthe first plurality of ports extending through the combustion chamberwall mixes with vaporized fuel discharged through the apertures in thetop wall of the fuel vaporizing chamber to form a stoichiometric ratioof mixed fuel and air thereby producing products of combustion havingboth maximum heat production and maximum fuel efficiency; the productsof combustion engaging the bottom wall and the outer surface of thecooking pot to effect maximum heat transfer thereto.
 10. The cookingstove according to claim 9 wherein the wall of the combustion chambercomprises a metal sheet defined by first and second ends, the first andsecond ends removably fastened together by rivets secured on the firstend for engagement with rivet receiving orifices on the second end. 11.The cooking stove according to claim 9 wherein the obturating devicecomprises a right cylindrical band movably coupled about the wall of thecombustion chamber, the band having a longitudinal dimension whichoperatively enables airflow through one of the first or second rows ofports while preventing airflow through the other of the first or secondrows of ports.
 12. The cooking stove according to claim 9 wherein themeans for supporting a cooking pot within the wall comprises at leastone rod extending through orifices perforated in the upper end of thewall and supported by the wall.
 13. A lightweight portable cooking stovecomprising the combination of: a combustion chamber comprising: asubstantially imperforate cylindrical wall having an upper end and alower end, the lower end for engaging a supporting surface; the wallhaving a defined diameter; and an opening and comprising a first row ofrelatively large substantially equally spaced ports and a second row ofrelatively small substantially equally spaced ports, the first andsecond rows of ports separated by a predetermined longitudinal distance;an obturating device supported on an longitudinally movable relative tothe wall for at least partially covering one of either the first row orthe second row of ports thereby controlling both the volume and rate ofair flow into selected ports of combustion chamber; and means forsupporting a cooking pot within the wall of the combustion chamberwherein a lower portion of the cooking pot is substantially locatedwithin the upper end of the wall of the combustion chamber; a fuelvaporizer supported by the support surface and axially aligned with thewall of the combustion chamber, the fuel vaporizer comprising: an innerfuel vaporizing chamber defined by a first enclosure having asubstantially conical shape having upper and lower ends, the upper endhaving a smaller diameter than the lower end, an outer surface, an innersurface, and a first imperforate bottom wall extending across theentirety of the lower end; an outer fuel receiving chamber surroundingthe inner fuel vaporizing chamber; at least one fuel passagewayextending between the inner fuel vaporizing chamber and the outer fuelreceiving chamber; the inner chamber axially aligned within the outerchamber; a top wall extending across the entirety of the upper end ofthe enclosure of the inner fuel vaporizing chamber, the top wallcomprising a plurality of apertures formed therethrough an substantiallyequally spaced intervals around the outside surface of the enclosure tofacilitate the passage of vaporized fuel from the inner fuel vaporizingchamber into the combustion chamber; a fuel vaporizer obturating devicemovably coupled about the outer fuel receiving chamber comprising acylindrical collar coupled about the outer chamber and having means formoving the obturating device between a vertically lowered position and avertically raised position relative to the outer chamber for regulatingairflow into the outer chamber thereby controlling the heat output ofthe fuel vaporizer; a cooking pot comprising a right circular cylinderhaving an outside diameter which is smaller than the defined diameter ofthe wall of the combustion chamber, the right circular cylinder of thecooking pot comprising an outer surface and an inner surface; thecooking pot further comprising a substantially planar bottom wallcomprising an extension of and extending substantially perpendicular tothe outer wall of the cooking pot; whereby air entering the firstplurality of ports extending through the combustion chamber wall mixeswith vaporized fuel discharged through the apertures in the top wall ofthe fuel vaporizer to form a stoichiometric ratio of mixed fuel and airthereby producing products of combustion having both maximum heatproduction and maximum fuel efficiency; the products of combustionengaging the bottom wall and outer surface of the cooking pot to effectmaximum heat transfer.
 14. The cooking stove according to claim 13wherein the wall of the combustion chamber comprises an aluminum sheetdefined by first and second ends, the first and second ends removablyfastened together by rivets secured on the first end for engagement withrivet receiving orifices on the second end.
 15. The cooking stoveaccording to claim 13 wherein the obturating device comprises a rightcylindrical band movably coupled about the wall of the combustionchamber, the band having a longitudinal dimension which operativelyenables airflow through one of the first or second rows of ports whilepreventing airflow through the other of the first or second rows ofports.
 16. The cooking stove according to claim 13 wherein the means forsupporting a cooking pot within the wall comprises at least one rodextending through orifices perforated in the upper end of the wall andthereafter supported by the wall.
 17. A lightweight portable cookingstove comprising the combination of: a combustion chamber comprising: asubstantially imperforate cylindrical wall having an upper end and alower end, the lower end for engaging a supporting surface; and the wallhaving a defined diameter; an outer cylinder surrounding the lower endof the substantially imperforate cylindrical wall and extending adefined distance therebelow, the defined distance forming an openingbeneath the cylindrical wall for enabling airflow into the combustionchamber, the outer cylinder for controlling both the volume and rate ofair flow into the combustion chamber through the opening; and means forsupporting a cooking pot within the wall of the combustion chamberwherein a lower portion of the cooking pot is substantially locatedwithin the upper end of the wall of the combustion chamber; a fuelvaporizer supported by the support surface and axially aligned with thewall of the combustion chamber, the fuel vaporizer comprising: an innerfuel vaporizing chamber defined by a first enclosure having asubstantially conical shape having upper and lower ends, the upper endhaving a smaller diameter than the lower end, an outer surface, an innersurface, and a first imperforate bottom wall extending across theentirety of the lower end; an outer fuel receiving chamber surroundingthe inner fuel vaporizing chamber; at least one fuel passagewayextending between the inner fuel vaporizing chamber and the outer fuelreceiving chamber; the inner chamber axially aligned within the outerchamber; a top wall extending across the entirety of the upper end ofthe enclosure of the inner fuel vaporizing chamber, the top wallcomprising a plurality of apertures formed therethrough at substantiallyequally spaced intervals around the outside surface of the enclosure tofacilitate the passage of vaporized fuel from the inner fuel vaporizingchamber into the combustion chamber; a fuel vaporizer obturating devicemovably coupled about the outer fuel receiving chamber comprising acylindrical collar coupled about the outer chamber and having means formoving the obturating device between a vertically lowered position and avertically raised position relative to the outer chamber for regulatingairflow into the outer chamber thereby controlling the heat output ofthe fuel vaporizer; a cooking pot comprising a right circular cylinderhaving an outside diameter which is smaller than the defined diameter ofthe wall of the combustion chamber, the right circular cylinder of thecooking pot comprising an outer surface and an inner surface; thecooking pot further comprising a substantially planar bottom wallcomprising an extension of and extending substantially perpendicular tothe outer wall of the cooking pot; whereby air entering the openingbeneath the combustion chamber wall mixes with vaporized fuel dischargedthrough the apertures in the top wall of the fuel vaporizer to form astoichiometric ratio of mixed fuel and air thereby producing products ofcombustion having both maximum heat production and maximum fuelefficiency; the products of combustion engaging the bottom wall andouter surface of the cooking pot to effect maximum heat transfer. 18.The cooking stove according to claim 17 wherein the wall of thecombustion chamber comprises an aluminum sheet defined by first andsecond ends, the first and second ends removably fastened together byrivets secured on the first end for engagement with rivet receivingorifices on the second end.
 19. The cooking stove according to claim 17wherein the means for supporting a cooking pot within the wall comprisesat least one rod extending through orifices perforated in the upper endof the wall and thereafter supported by the wall.